Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs

Failed to fetch cdrom:[Ubuntu 7.10 _Gutsy Gibbon_ – Release i386 (20071016)]/dists/gutsy/main/binary-i386/Packages.gz Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs

Failed to fetch cdrom:[Ubuntu 7.10 _Gutsy Gibbon_ – Release i386 (20071016)]/dists/gutsy/restricted/binary-i386/Packages.gz Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs

Reading package lists… Done

E: Some index files failed to download, they have been ignored, or old ones used instead.

taufanlubis@toshiba:~$

If you want to use the DVD, you have to include it in Ubuntu Software Sources (System > Administration > Software Sources > Third party software > Add CD-ROM)